Powertrain, generic (extended)

P2753 Transmission Fluid Cooler Control Circuit/Open

Check engine lightOn
EmissionsRelevant
Drive cycleNot required
Limp modeNo

P2753 is set when the control module finds no closed circuit to the actuator that regulates transmission fluid cooling, usually an electrically switched coolant valve that opens or shuts the flow of engine coolant through the fluid heat exchanger. With the valve output open, the module cannot steer warm-up or cooling of the gearbox oil. Audi uses the code on the 2023 Q7 and SQ7: diagnostic notice AOS-26-09 of February 2026 supplies a tester hotfix because P275300 was stored without a matching guided test. Under CARB rules such an output must be checked for circuit continuity. Unlike P2754 and P2755 no short is involved, only missing continuity from a broken wire, loose pin or burnt coil. Fluid may run hotter under load or warm up more slowly.

Likely causes

Open coil in the transmission fluid cooling valve
Loose or corroded connector at the valve, often after coolant contact
Broken control wire between module and valve
Faulty output stage in the control module

Symptoms

  • Check engine lamp on
  • Transmission fluid warms up slowly or runs hot when towing
  • Transmission overheat warning in severe cases

Repair estimate

DifficultyMediumDIY possible
Parts and labour€40–350
Time0.5–2 h

Typical range across vehicles; the real cost depends on what the testing finds.

Parts involved

trans fluid cooler valvewiring harness

Related codes

P2754P2755P0218P0711

References: static.nhtsa.gov, law.cornell.edu.